1. Field of the Invention
This invention relates to apparatus used in industrial automated assembly line and packaging operations, and more particularly, to machines that use pneumatics for picking up and placing small, light weight parts.
2. Background
A number of pneumatic prior art devices are presently used for picking up and placing small, light weight items; particularly items such as labels for automated labeling of packages or containers.
A typical current device uses a box with a screen on the bottom and a suction fan on the top to hold a label prior to dispensing with a blast of air. The box is very bulky and is designed to be fixed to a label machine, making it difficult to conform the device to other applications. An electric fan motor, is also a potential fire hazard in some industrial environments.
Another device uses a Venturi vacuum generator to create a low pressure in a suction cup. The difference between the low pressure created by the Venturi and the atmospheric pressure presses the part to be lifted into the suction cup. A blast air supply for tamping may be attached.
Both types of devices contact the lifted parts, if only briefly. Both types of devices also may be characterized as having holding periods which include times for the suction or vacuum level to build up and to decay, allowing a machine to initiate a following step. Thus, for these types of lifting/tamping devices, there is a minimum lifting time that can not be shortened to increase item processing speed.
Some problems that are common to the known devices are:                damage to or distortion of items held to the device during lift periods;        clogging of suction openings with debris;        leakage of air into Venturi suction cups, or leakage of suction air resulting in failure to lift a part;        failure to lift parts having perforations;        difficulty in adjustment for varied part applications;        and,        much down time for routine maintenance.        
The present invention device incorporates a simple design that does not contact lifted items, solves these problems and greatly reduces device and installation costs.